Design of ultrasonic attenuation sensor with focused transmitter for density measurements of a slurry in a large steel pipeline

To design an ultrasonic sensor to measure the attenuation and density of slurry carried by a large steel pipeline (diameter up to 70 cm) is the goal of this research. The pitch-catch attenuation sensor, placed in a small section of the pipeline, contains a send unit with a focused transducer that focuses the ultrasound to a small region of the receive unit on the opposite wall. The focused transducer consists of a section of a sphere (base ∼12 cm) on the outer side of the send unit and a 500 kHz piezoelectric shell of lead zirconate titanate epoxied to it. The Rayleigh surface integral is used to calculate the pressure in steel and in water (slurry). An incremental method to plot the paths of ultrasonic rays shows that the rays focus where expected. Further, there is a region where the parallel rays are perpendicular to the wall of the receive unit. Designs for pipeline diameters of 25 and 71 cm show that the pressure in water at the receive transducer is about 17 times that for a pitch-catch system using 5 cm diameter disk transducers. The enhanced signal increases the sensitivity of the measurements and improves the signal-to-noise ratio.

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The mapping between phonological categories and acoustic cues in the production of English obstruents

Phonological feature structure is inherently multidimensional, and decades' worth of research in acoustic phonetics has documented both the complex mappings between features and associated acoustic cues as well as the prosodic modulation of these mappings. Most previous studies have focused on how the mean values of acoustic cues vary in complex ways across multiple phonological dimensions, relying on strong assumptions of statistical independence and/or homogeneity of variance across acoustic measures. The present study probes these assumptions by exploring the mapping between phonological voicing, place, and manner features and 8 acoustic cues from tokens of 14 English consonants produced in onset and coda position. Multivariate linear models exhibiting a variety of feature-cue mappings and between-cue statistical relationships were fit to this corpus of acoustic data. Model comparisons indicate that the best statistical description of the data requires pervasive interactions between features with respect to both the locations and the shapes of phonological categories. The implications of these results for work on the production and perception of phonological contrasts is discussed.

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Effect of multi-electrode configuration on sensitivity to interaural timing differences in bilateral cochlear-implant users

Recent psychophysical studies in bilateral cochlear implant users have shown that interaural timing difference (ITD) sensitivity with electrical stimulation varies depending on the place of stimulation along the cochlear array. While these studies have measured ITD sensitivity at single electrode places separately, it is important to understand how ITD sensitivity is affected when multiple electrodes are stimulated together because multi-electrode stimulation is required for representation of complex sounds. Multi-electrode stimulation may lead to poorer overall performance due to interference from places with poor ITD sensitivity, or from channel interaction due to electrical current spread. Alternatively, multi-electrode stimulation might result in overall good sensitivity if listeners can extract the most reliable ITD cues available. ITD just noticeable differences (JNDs) were measured for different multi-electrode configurations. Results showed that multi-electrode ITD JNDs were poorer than ITD JNDs for the best single-electrode pair. However, presenting ITD information along the whole array appeared to produce better sensitivity compared with restricting stimulation to the ends of the array, where ITD JNDs were comparable to the poorest single-electrode pair. These findings suggest that presenting ITDs in one cochlear region only may not be optimal for maximizing ITD sensitivity in multi-electrode stimulation.

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The psychophysics of roughness applied to dysphonic voice

Roughness is a sound quality that has been related to the amplitude modulation characteristics of the acoustic stimulus. Roughness also is considered one of the primary elements of voice quality associated with natural variations across normal voices and is a salient feature of many dysphonic voices. It is known that the roughness of tonal stimuli is dependent on the frequency and depth of amplitude modulation and on the carrier frequency. Here, it is determined if similar dependencies exist for voiced speech stimuli. Knowledge of such dependencies can lead to a better understanding of the acoustic characteristics of vocal roughness along the continuum of normal to dysphonic and may facilitate computational estimates of vocal roughness. Synthetic vowel stimuli were modeled after talkers selected from the Satloff/Heman-Ackah disordered voice database. To parametrically control amplitude modulation frequency and depth, synthesized stimuli had minimal amplitude fluctuations, and amplitude modulation was superimposed with the desired frequency and depth. Perceptual roughness judgments depended on amplitude modulation frequency and depth in a manner that closely matched data from tonal carriers. The dependence of perceived roughness on amplitude modulation frequency and depth closely matched the roughness of sinusoidal carriers as reported by Fastl and Zwicker [(2007) Psychoacoustics: Facts and Models, 3rd ed. (Springer, New York)].

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Measuring two-phase particle flux with a multi-frequency acoustic Doppler profiler

A methodology is developed and tested for simultaneously extracting time-resolved one-dimensional profiles of the mass-concentration and velocity of two different particle types in a mixed suspension, using a multi-frequency pulse-to-pulse coherent Doppler instrument. The technique involves inversion of a model for frequency-dependent acoustic backscatter amplitude and phase. Results are presented from a laboratory settling column experiment, measuring a mixture of polystyrene beads (slowly-settling, strongly-scattering) and glass beads (quickly-settling, weakly-scattering) in a vertical pipe section.

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Toxic secretions from intracranial tumor damage the inner ear

Researchers discover new mechanism of vestibular schwannoma that causes hearing loss, introduce new direction for therapy.

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Toxic secretions from intracranial tumor damage the inner ear

Researchers discover new mechanism of vestibular schwannoma that causes hearing loss, introduce new direction for therapy.

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The p.Cys169Tyr variant of connexin 26 is not a polymorphism.

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The p.Cys169Tyr variant of connexin 26 is not a polymorphism.

Hum Mol Genet. 2015 May 1;24(9):2641-8

Authors: Zonta F, Girotto G, Buratto D, Crispino G, Morgan A, Abdulhadi K, Alkowari M, Badii R, Gasparini P, Mammano F

Abstract
Mutations in the GJB2 gene, which encodes the gap junction protein connexin 26 (Cx26), are the primary cause of hereditary prelingual hearing impairment. Here, the p.Cys169Tyr missense mutation of Cx26 (Cx26C169Y), previously classified as a polymorphism, has been identified as causative of severe hearing loss in two Qatari families. We have analyzed the effect of this mutation using a combination of confocal immunofluorescence microscopy and molecular dynamics simulations. At the cellular level, our results show that the mutant protein fails to form junctional channels in HeLa transfectants despite being correctly targeted to the plasma membrane. At the molecular level, this effect can be accounted for by disruption of the disulfide bridge that Cys169 forms with Cys64 in the wild-type structure (Cx26WT). The lack of the disulfide bridge in the Cx26C169Y protein causes a spatial rearrangement of two important residues, Asn176 and Thr177. In the Cx26WT protein, these residues play a crucial role in the intra-molecular interactions that permit the formation of an intercellular channel by the head-to-head docking of two opposing hemichannels resident in the plasma membrane of adjacent cells. Our results elucidate the molecular pathogenesis of hereditary hearing loss due to the connexin mutation and facilitate the understanding of its role in both healthy and affected individuals.

PMID: 25628337 [PubMed - indexed for MEDLINE]

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The p.Cys169Tyr variant of connexin 26 is not a polymorphism.

Related Articles

The p.Cys169Tyr variant of connexin 26 is not a polymorphism.

Hum Mol Genet. 2015 May 1;24(9):2641-8

Authors: Zonta F, Girotto G, Buratto D, Crispino G, Morgan A, Abdulhadi K, Alkowari M, Badii R, Gasparini P, Mammano F

Abstract
Mutations in the GJB2 gene, which encodes the gap junction protein connexin 26 (Cx26), are the primary cause of hereditary prelingual hearing impairment. Here, the p.Cys169Tyr missense mutation of Cx26 (Cx26C169Y), previously classified as a polymorphism, has been identified as causative of severe hearing loss in two Qatari families. We have analyzed the effect of this mutation using a combination of confocal immunofluorescence microscopy and molecular dynamics simulations. At the cellular level, our results show that the mutant protein fails to form junctional channels in HeLa transfectants despite being correctly targeted to the plasma membrane. At the molecular level, this effect can be accounted for by disruption of the disulfide bridge that Cys169 forms with Cys64 in the wild-type structure (Cx26WT). The lack of the disulfide bridge in the Cx26C169Y protein causes a spatial rearrangement of two important residues, Asn176 and Thr177. In the Cx26WT protein, these residues play a crucial role in the intra-molecular interactions that permit the formation of an intercellular channel by the head-to-head docking of two opposing hemichannels resident in the plasma membrane of adjacent cells. Our results elucidate the molecular pathogenesis of hereditary hearing loss due to the connexin mutation and facilitate the understanding of its role in both healthy and affected individuals.

PMID: 25628337 [PubMed - indexed for MEDLINE]

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Cultural Adaptation Quality of Family Life Scale for the Brazilian Portuguese.

Cultural Adaptation Quality of Family Life Scale for the Brazilian Portuguese.

Codas. 2015 Dec;27(6):534-540

Authors: Jorge BM, Levy CC, Granato L

Abstract
Purpose To culturally adapt the Family Quality of Life Scale to the Brazilian Portuguese version and evaluate the instrument reliability and family quality of life of those who have children with hearing loss. Methods The process of cultural adaptation of the scale followed the steps of the Guidelines for the Process of Cross-Cultural Adaptation of Self-Report Measure. It was conducted in three stages: translation, back translation, and application in a pilot sample, as a way to check the comprehension difficulties of the items. After it had been completed, it was administered to 41 families who have children with hearing loss and, with their results, the quality of life and reliability were analyzed based on the Cronbach's alpha statistical test. Results In the first version (translation), among the 25 items, there were differences between the translators only in four items; after the corrections, the second version was done (back translation), in which other four more differences were found. Finally, after the final corrections, the last version was developed and used in the pilot sample without differences. Thus, it was applied to families with deaf children, who believe to be satisfied as to their quality of life. The Cronbach's alpha test found that the scale shows a satisfactory reliability. Conclusion The Brazilian Portuguese version of the Family Quality of Life Scale is a tool of easy use and satisfactory reliability. The families are satisfied with their family quality of life.

PMID: 26691617 [PubMed - as supplied by publisher]

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Late morbidity in long-term survivors of childhood brain tumors: a nationwide registry-based study in Finland.

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Late morbidity in long-term survivors of childhood brain tumors: a nationwide registry-based study in Finland.

Neuro Oncol. 2015 May;17(5):747-56

Authors: Gunn ME, Lähdesmäki T, Malila N, Arola M, Grönroos M, Matomäki J, Lähteenmäki PM

Abstract
BACKGROUND: The population of long-term survivors of childhood brain tumors (BTs) is growing. The aim of our study was to evaluate late-appearing morbidity in BT survivors.
METHODS: Patients diagnosed with a BT at the age of 0-15 years between 1970 and 2004, and surviving at least 5 years, were identified from the Finnish Cancer Registry (n = 740). Their late new morbidity ≥ 5 years after cancer diagnosis was assessed using the Hospital Discharge Registry containing hospitalizations and outpatient visits in specialized health care settings. The morbidity of BT survivors was compared with that of the sibling cohort (n = 3615).
RESULTS: The 5-year survivors had a significantly increased hazard ratio (HR) for endocrine diseases (HR, 14.7), psychiatric disorders (HR, 1.8), cognitive and developmental disorders (HR, 16.6), neurological diseases (HR, 9.8), disorders of vision and hearing (HR, 10.5), and diseases of the circulatory system (HR, 2.7) compared with the sibling cohort. The HRs for disorders of musculoskeletal system (HR, 1.4) and diseases of the kidney (HR, 2.1) were not significantly increased. Radiation treatment did not explain all of the excess morbidity. Female survivors had a higher risk for disorders of vision and hearing (P = .046). Age at diagnosis did not show an effect on HRs. The HRs for endocrine diseases and disorders of vision or hearing loss were highest for survivors treated in the 1980s or later.
CONCLUSIONS: Pediatric BT survivors had significant neurocognitive consequences. This, together with the considerable risk for endocrine morbidity, will motivate us to organize systematic follow-up procedures for pediatric BT survivors.

PMID: 25422316 [PubMed - indexed for MEDLINE]

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Middle and inner ear malformations in two siblings exposed to valproic acid during pregnancy: a case report.

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Middle and inner ear malformations in two siblings exposed to valproic acid during pregnancy: a case report.

Int J Pediatr Otorhinolaryngol. 2014 Nov;78(11):2007-10

Authors: Van Houtte E, Casselman J, Janssens S, De Kegel A, Maes L, Dhooge I

Abstract
Valproic acid (VPA) is a known teratogenic drug. Exposure to VPA during the pregnancy can lead to a distinct facial appearance, a cluster of major and minor anomalies and developmental delay. In this case report, two siblings with fetal valproate syndrome and a mild conductive hearing loss were investigated. Radiologic evaluation showed middle and inner ear malformations in both children. Audiologic, vestibular and motor examination was performed. This is the first case report to describe middle and inner ear malformations in children exposed to VPA.

PMID: 25216807 [PubMed - indexed for MEDLINE]

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